The presence and severity of myelopathy can be evaluated by means of Transcranial Magnetic Stimulation (TMS), a neurophysiological method that allows the measurement of the time required for a neural impulse to cross the pyramidal tracts, starting from the cerebral cortex and ending at the anterior horn cells of the cervical, thoracic or lumbar spinal cord. This measurement is called Central Conduction Time (CCT). TMS can aid physicians to:[3]

determine whether myelopathy exists

identify the level of the spinal cord where myelopathy is located. This is especially useful in cases where more than two lesions may be responsible for the clinical symptoms and signs, such as in patients with two or more cervical disc hernias[4]

follow-up the progression of myelopathy in time, for example before and after cervical spine surgery

TMS can also help in the differential diagnosis of different causes of pyramidal tract damage.[5]